Epidemiologic studies of alcohol and health suggest that moderate drinking is associated with benefits, especially related to cardiovascular disease, stimulating a demand for guidelines on moderate drinking to be used in evaluating the safety of individuals' drinking and in planning public health policy. Despite the fact that guidelines are written in terms of three dimensions, usual quantity (drinks per drinking day), usual frequency, and binge drinking, little information is currently available on risks of health and psychosocial consequences associated with specific patterns of drinking defined by these three dimensions. It is proposed that drinking patterns prevalent in the adult U.S. population be defined in terms of usual quantity, usual frequency, and binge drinking; that rates of health and psychosocial consequences associated with these patterns be determined; and that factors moderating the relation of pattern to risk, such as age, gender, family history of alcohol problems, and social drinking norms (related to wet and dry regions, race, and ethnicity), be investigated. In Year 1 studies utilizing cluster analytic and segmentation techniques (CHAID) will be based on data from the 1988 National Health Information Survey (NHIS; N=43,809). The NHIS routinely assesses health status in the past 12 months. In addition, the 1988 Alcohol Supplement included questions on alcohol consumption, alcohol experiences used to assess criteria for DSM-III-R diagnoses of alcohol disorders, and on a family history of alcohol problems. It also includes retrospective data on drinking that will permit investigation of causal relations between drinking patterns and consequences. In Year 2 findings will be confirmed in other national and regional alcohol surveys selected to extend, as well as replicate them, by examining patterns among individuals: who were assessed for risk of chronic disease, Center for Clinical & Medical Epidemiology of Alcohol; blacks and Hispanics, 1984 National Alcohol Survey selected for national studies of warning labels; over 65 providing retrospective data. These studies will provide information on risks associated with drinking patterns that can be directly related to guidelines for moderate drinking; they will extend studies on risk to include both health and psychosocial consequences associated with patterns; they will address important factors that modify risk and need to be addressed in the guidelines; and they will identify patterns that are particularly harmful for targeted intervention.